Straight layered hair

I washed my hair, detangled and rinsed everything out. I added IC hair polisher lightly over most of my strands then kept rubbing and combed to clump hair and distribute the IC. I didn't have time to air dry it so I used the "cool" setting on my blowdryer. Removed most of the water, and when i woke up I detangled any tangles, sectioned out my hair. Maybe it's because I work slow but this took three hours to straighten but will last me about a week or so.